But it may appears because of another service on server, which catch incoming files, so this error is not critical and Ok.

But today morning WinSCP was totally crashed and generate this error

winscp> option batch on
batch on
winscp> option confirm off
confirm off
winscp> open SFTP://XXXX:xxxxx@XX.XX.XX.XX:2222 -hostkey="ssh-dss 1024 XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX:XX"
Searching for host...
Connecting to host...
Host is not communicating for more than 15 seconds. Still waiting...
Warning: Aborting this operation will close connection!
(A)bort: Abort
Terminated by user.
winscp> ls
No session.
winscp> put C:\WINDOWS\TEMP\tmpF.tmp /sl01/min_day.js
No session.
winscp> exit

All attempts has the same result. Communication is Ok, SFTP server is works and accessible, no changes in port forwarding or something similar was made. PC restart does not help.
When I tried to use WinSCP.exe after input login data and press login I got "Invalid Access to memory", may be caused by Windows version limitation and it's not critical.

Windows XP Embedded SP 3

Another PC with the same configuration works fine (except point "Invalid Access to memory").